Sheaves, Tension & Safety Components · GROOVE
Sheave Groove Wear & Regrooving
Where rope life is won and lost.
Sheave grooves wear just as ropes do: profiles deepen and distort, undercuts erode, and grooves wear unevenly across the set. Worn grooves mis-seat and overload ropes, destroy new sets prematurely and erode traction. Regrooving machines the grooves back to true, matched profile — restoring the geometry rope and sheave were designed to share.
The explainer
Watch how it works.
Schematic · loops automatically
1Wires press into iron
Hard rope, softer sheave: every trip removes a little groove — polishing first, then deepening.
2The undercut retreats
The grip-giving slot wears back toward a round seat; traction margin follows it out the door.
3Grooves wear unequally
Different depths mean different effective diameters — ropes forced to travel at different speeds on one shaft.
4Imbalance feeds back
The deep groove drags, tensions diverge, wear accelerates — and new ropes inherit all of it.
5Machine back to true
Regrooving cuts every groove to the same profile and pitch diameter, undercut restored — the system reset.
How it works, plainly
Every trip presses hardened rope wires into softer sheave iron under hundreds of kilograms per groove. The groove polishes, then deepens; a U-groove’s undercut — the slot that gives the profile its grip — wears back toward a plain round seat, quietly surrendering traction.
Uneven wear is the killer detail. Grooves never wear identically, so ropes ride at different diameters of an effectively different pulley: the rope in the deepest groove travels less per revolution than its neighbours, so the set drags itself into permanent tension imbalance and accelerated wear — new ropes inherit the problem on day one.
Regrooving is machining, not dressing: metal is cut until every groove presents the same true profile at the same pitch diameter, undercuts restored to specification. It is viable while enough rim material remains; beyond that, honest practice replaces the sheave. Either way, the rule stands — grooves are assessed whenever ropes are, because the pair wear as a system.
Where this matters
On the job
- Pre-re-roping groove assessment (every survey)
- Diagnosing premature wear on newish ropes
- Restoring traction margins without machine replacement
Standards & references
| Reference | Covers |
|---|---|
| Design profiles | U, undercut-U and V groove geometries per installation design |
| EN 81 context | The traction requirements groove geometry serves |
Re-Ropes gauges groove profiles as standard survey practice and machines sheaves and diverters back to true — or supplies replacements where the iron is spent.
How can I tell grooves are worn without gauges?
Look for ropes sitting at different heights across the sheave, brightly polished seats, rounded undercut edges, and tension imbalance that keeps returning. Any of these earns proper gauging — the measurements decide.
Is regrooving always possible?
No — it consumes rim material and reduces pitch diameter slightly, so it is viable only while enough sound metal remains to restore full profile at a safe diameter. Beyond that, sheave replacement is the correct call, and we supply it.
Should regrooving happen before or with a re-rope?
With it, ideally: machining first, new ropes into true grooves the same visit. New ropes into worn grooves is the industry’s classic false economy.
Lift Industry Specialists
Questions about groove on your installation?
Describe the lift and the symptom — an engineer who has seen it before will tell you what it means and what it costs to fix.